Answer:
A
Step-by-step explanation:
Consider the right triangle formed by the diagonal
The diagonal is the hypotenuse of the right triangle.
Using Pythagoras' identity to find the diagonal d
The square on the hypotenuse is equal to the sum of the squares on the other 2 sides, that is
d² = 70² + 50² = 4900 + 2500 = 7400 ( take the square root of both sides )
d = [tex]\sqrt{7400}[/tex] ≈ 86 → A
